BMW 850 CI Fuelling Problem

BMW 850 CI Fuelling Problem

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Discussion

Tunamain

Original Poster:

4 posts

117 months

Monday 28th July 2014
quotequote all
Hey there
I've just acquired a 1994 BMW 850CI which has been standing still for over 5 years.
At this point I am only interested in getting it to run, it has good compression and sparks fine but no fuel getting through.
Does anyone have any suggestions of whether there are any known issues with fuel pumps "sticking" over time or dodgy relays?

thatdude

2,655 posts

127 months

Monday 28th July 2014
quotequote all
COuld well be blocked up injectors from fuel deposits settling out. The thing is, were have the deposits settled out! Is there a fuel filter to change?

Tunamain

Original Poster:

4 posts

117 months

Monday 28th July 2014
quotequote all
thanks for the suggestions, the fuel filter is clear but not sure about the injectors yet though, it appears that the pump just doesn't run, is there a fuel cut-off switch anywhere on these?

kambites

67,553 posts

221 months

Monday 28th July 2014
quotequote all
Doesn't those V12s have an entirely independent fuelling system for each bank?

Tunamain

Original Poster:

4 posts

117 months

Monday 28th July 2014
quotequote all
I've read different things bout the fuelling systems, one person has told me that there is only one pump and another that there may be two pumps, either way I haven't removed the rear seat yet to have a look underneath to see for myself.....hopefully will do that later today.

Pickled

2,051 posts

143 months

Monday 28th July 2014
quotequote all
Stick your VIN number in here and select the fuel system, it'll give you an exploded view of the parts

http://www.realoem.com/bmw/select.do

Tunamain

Original Poster:

4 posts

117 months

Monday 28th July 2014
quotequote all
thanks pickled

B'stard Child

28,381 posts

246 months

Tuesday 29th July 2014
quotequote all
Tunamain said:
Hey there
I've just acquired a 1994 BMW 850CI which has been standing still for over 5 years.
At this point I am only interested in getting it to run, it has good compression and sparks fine but no fuel getting through.
Does anyone have any suggestions of whether there are any known issues with fuel pumps "sticking" over time or dodgy relays?
Can you hear the pump running?

Have you checked for pressure at the rail? - normally a schreader type valve on the fuel rail (under the plastic engine cover)

Injectors themselves can stick over time when not used - sometimes a few little light taps on the metal bodies of the injector can "bring them back to life" if it's done at the same time as trying to start then engine

If the fuel filter is anything like the E38/E39 one - it's huge, expensive to replace as it's viewed by BMUU as "lifetime"